The present invention relates to recorders such as printers and, more particularly, to such printers depositing materials on recording sheets from a transfer ribbon based materials supply to provide a print image.
The use of personal computers and, correspondingly, desk top printers controlled in part by such computers has increased very rapidly over the last several years. Many different printing technologies have been developed for these devices beyond that used in the impact printers initially performing in this role, including ink jet, thermal wax transfer and thermal diffusion, or dye sublimation, printing technologies.
These last technologies have been especially important in the growth of color printers, those having the capability of providing a colored image on a recording medium. The order of listing of these printing technologies above is typically the order of the quality of the results obtained in using them with ink jet technology generally providing the poorest quality of these technologies, and thermal diffusion giving the best. The order of listing is typically also the order of cost with ink jet printers generally being cheapest and thermal diffusion printers being the costliest.
The desire for high quality in images recorded by such printers has led to those printers having often provided therein substantial computing capabilities in their own right to permit close control of electrical currents through the resistors in the thermal printhead which, in each supplying heat to the coloring material source to direct material therefrom onto the recording sheet, leads to each effectively providing a corresponding color constituent of a pixel, on that sheet. In addition, extensive mechanical systems with expensive components such as high speed and high precision stepper motors, are usually used in such printers. Among such mechanical systems typically used in such printers is a supply ribbon transport system, at least in the last two types of printer technologies listed above, thermal wax transfer and thermal dye diffusion. Such a system is used to transport the next of a repeating sequence of color panels under the thermal printhead in the printer each having therein the coloring materials in or on the ribbon fabric to be supplied for deposition on a recording sheet to thereby provide a corresponding primary subtractive color on that sheet for a print image being formed thereon.
Such supply ribbons are usually provided wound about a ribbon core typically formed of plastic or relatively thick cardboard. Because inserting such a core into a printer, and winding the free end of the ribbon a bit about another ribbon core, the take-up core, is often a messy and somewhat intricate operation, supply ribbons are often supplied in a ribbon cassette, or cartridge, in which the supply ribbon and two cores are provided, the supply core and the take-up core. Initially, most of the supply ribbon is wound about the supply core with a small portion wound about the take-up core, and the cassette is inserted as a whole into a printer.
Inserting, or removing, a supply ribbon cassette into or from a printer, however, is also often a somewhat involved task. The interior of a printer is typically densely filled with various components, and often quite exact positioning is required in inserting a cassette to permit its engagement with a drive mechanism for the take-up core while fitting it into the available space. Further, there must be provision made for having the inserted supply ribbon being ultimately positioned between the printhead and the recording sheet. Removal of the cassette usually brings similar problems in the opposite direction. Thus, there is a desire for a convenient arrangement for inserting supply ribbon cassettes into, and removing them from, a printer.